-LRB- CNN -RRB- -- Charles de Gaulle Airport in Paris was rebounding Saturday after hundreds of flights were canceled because of a shortage of de-icing fluid during snow and ice that snarled air traffic across Europe , authorities said .

Flight delays at de Gaulle were expected to decrease as the day went on . Officials could not give an exact number of flight cancellations .

The weather improved Saturday and shipments of de-icing fluid from Charlotte , North Carolina , and Germany , will help alleviate future problems , officials said .

Nathalie Kosciusko-Morizet , minister for transportation and ecology , said she wants more information on the fluid shortage .

About 300 people who spent the night at the airport were provided with food and blankets , officials said . Transport ministry official Thierry Mariani paid them a visit and volunteers provided stuff animals for children and gifts of chocolate .

Some passengers and others were critical of what happened at de Gaulle , but officials blamed the situation largely on the weather .

Air France CEO Pierre-Henri Gourgeoan told the news agency AFP the airline had not been informed of the problems .

`` It is surprising and somewhat -LSB- impermissible -RSB- that an airport such as Roissy Charles de Gaulle could experience such a supply problem . It is an isolated case in Europe , '' said Gourgeoan .

Meanwhile , the Brussels , Belgium , airport reported that operations were nearly back to normal Saturday , with two of three runways operational .

Gatwick Airport and Heathrow Airports in London said airlines were operating , but some delays or cancellations were possible .

Airports across Europe are still struggling to get passengers to their destinations after they were snarled by unexpected snow over the weekend .

Nearly 2,000 passengers at de Gaulle were moved from Terminal 2E to other parts of the airport on Friday because of the weight of snow on a roof , French authorities said , calling the measure `` preventative . ''

Part of the roof of that terminal collapsed in 2004 , shortly after the state-of-the-art building was inaugurated . Four people were killed , media reports at the time said .

About a foot of snow had fallen on the roof Friday by the time authorities decided to close the terminal , French media reports said .

French authorities earlier Friday asked airlines to cancel half their morning flights to and from the airport because the de-icing fluid was running low . That led to the cancellation of 400 flights Friday morning -- 200 arrivals and 200 departures .

Then , early in the afternoon , authorities asked airlines to scrap a third of their flights for the rest of the day .

Charles de Gaulle is the second busiest airport in Europe , after Heathrow in London .

Paris ' second airport , Orly , has not had to cancel flights because it is not running out of glycol , which is using for de-icing , authorities said .

CNN 's Niki Cook and Per Nyberg contributed to this report .

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NEW : Officials will investigate de-icing fluid shortage

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Christmas Day brings smoother operations at Charles de Gaulle Airport

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About a foot of snow falls on the de Gaulle roof , forcing a partial evacuation

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European airports are recovering from long delays